body, html{
line-height: 1;
font-family: 'PingFang SC', 'STHeitiSC-Light', 'Helvetica-Light', arial, sans-serif, 'Droid Sans Fallback';
user-select: none;
-webkit-tap-highlight-color: transparent;
background: #222;
color: #fff;}

.flex{display: flex;}
.flex-vertical{display: flex;flex-direction:column;}
.flex-vertical-center{align-items: center;}
.flex-align-center{justify-content:center;}
.flex-1{flex:1;}
.flex-between{justify-content: space-between;}
.flex-around{justify-content: space-around;}
.flex-right{flex-direction: row-reverse;}
  